In recent years, in the communication performed by interconnecting a plurality of carriers (hereinafter referred as “interconnect communication”), new interconnect forms or settlement methods are being devised as new carriers enter the market or new communication services are created.
As a rule, the settlement among carriers that occurs when the interconnect communication is performed and that involves the charges for using facilities has been effected only among the carriers directly connected. Hence, no transfer of charges is carried out among the carriers indirectly connected except for special occasions.
This will be specifically explained, taking as an example, a case where a message is transmitted using the line facilities of a first carrier and goes through line facilities of a second carrier and a third carrier in turn and reaches a receiver.
In this case, the first carrier is entitled to bill the transmitter for the communication charge. The second carrier is entitled to bill the first carrier for having used its line facilities. The third carrier is entitled to bill the first carrier and the second carrier, respectively, for having used its line facilities. Although the third carrier can recognize that the second carrier has used their line facilities, the third carrier has difficulties to recognize that the first carrier has also used their line facilities.
Therefore, since the third carrier cannot fully recognize the communication, they can bill only the second carrier for having used their line facilities, and they cannot bill the first carrier for having used their line facilities.
Furthermore, recent interconnect forms and settlement methods are usually more complicated than existing interconnect forms and settlement methods. Accordingly, there has been a demand for apparatuses that are able to quickly and flexibly cope with such interconnect forms or settlement methods.